ZCZC MIATCDEP4 ALL
TTAA00 KNHC DDHHMM

Tropical Storm Mario Discussion Number   9
NWS National Hurricane Center Miami FL       EP142019
900 AM MDT Thu Sep 19 2019

The intensity of Mario is still 55 kt, based on a blend of objective
and subjective satellite intensity fixes, but these estimates likely
have a higher-than-normal uncertainty. Recent microwave and
first-light visible imagery implies that the low-level center of
Mario may now be displaced to the east of most of its deep
convection, and if this is actually the case, the winds may very
well have decreased since the last advisory.

Mario is currently embedded within low- to mid-layer southwesterly
flow and this should cause the cyclone to move generally
northeastward or north-northeastward for the next day or two. What
happens after that depends largely on Lorena. The odds that Mario
(or its remnants) will directly interact with Lorena (or its
remnants) have increased, but it is still unclear whether one
cyclone will absorb the other or if they will have a binary
interaction and rotate around one another. Confidence in the
forecast is therefore low, but will hopefully increase later today
after a reconnaissance plane provides more information about the
state of Lorena. The NHC forecast lies near the middle of the vast
guidance envelope and keeps Mario as a distinct system through day
5, but significant changes may be required to the track forecast
later today.

The intensity forecast is no clearer. Microwave imagery overnight
showed that Mario had once again developed a well-defined convective
inner-core. However, more recent imagery this morning suggests that
the tropical storm has become strongly tilted with height. The
poorly organized vertical structure should prevent the cyclone from
significant strengthening in the short term and moderate to strong
vertical wind shear is expected to continue for the next several
days. The official intensity forecast is quite a bit lower than the
previous one. It now lies closer to the intensity consensus but it
should be noted that it is too soon to completely rule out Mario
powering up to hurricane strength at some point during the next
several days.


FORECAST POSITIONS AND MAX WINDS

INIT  19/1500Z 16.5N 111.5W   55 KT  65 MPH
 12H  20/0000Z 17.2N 111.2W   60 KT  70 MPH
 24H  20/1200Z 18.0N 110.7W   60 KT  70 MPH
 36H  21/0000Z 19.0N 110.6W   55 KT  65 MPH
 48H  21/1200Z 20.2N 111.8W   55 KT  65 MPH
 72H  22/1200Z 22.1N 114.3W   45 KT  50 MPH
 96H  23/1200Z 24.0N 117.0W   35 KT  40 MPH
120H  24/1200Z 25.0N 119.0W   25 KT  30 MPH...POST-TROP/REMNT LOW

$$
Forecaster Zelinsky

NNNN